Introduction

Welcome to the home of Email Hippo technical documents for our ASSESS API. From here you can access full information about the API, view code in multiple languages and get started with your own integration.

About Email Hippo

Email Hippo is an email intelligence and data services provider that’s trusted by thousands of businesses and holds international security accreditations.

We deliver accurate cloud-based email validation and domain profiling. API use cases include data cleansing on demand or in real-time, fraud prevention and user signposting scenarios to improve user experience and build effective communication processes.

Our monitoring and detection of disposable email addresses is unrivalled.

Email Hippo website

About our APIs

> 99.99% uptime

Fully load balanced and automatic fail-over systems dispersed across multiple data centers in multiple regions deliver enterprise-grade resilience.

Easy integration

Take a look at our enpoints and code samples to see how quick and easy it is to integrate with our services.

Fast, transparent response times

Every query response includes stopwatch data that shows the time taken to execute the request. Typical queries are answered in under 0.5 seconds.

Unrivalled performance

Strategic data centers in Europe, aggressive caching, global network delivery optimization and cloud-based auto-scaling deliver outstanding performance.

Thoughtful versioning

Endpoints are ‘versioned’ allowing the release of new functionality without forcing customers to change or break if they are committed to integrating with legacy endpoints.

Service Status

For information on the status and performance of our services visit status.emailhippo.com.

Service Status Page

ASSESS Pre-fraud API

The next generation of the award-winning Email Hippo Trust Score; ASSESS is a scalable pre-fraud system for businesses from entry to enterprise levels. It delivers results via an API that’s integrated at the point where users sign-up and enter an email address. ASSESS explores the data behind every sign-up, looking for ‘tells’ and assigning a numeric level of risk to every result. The aggregated results are produced as a single Trust Score, enabling businesses to detect potentially risky sign-ups and take action accordingly.

Common features:

• Progressive verification using multiple verification processes including:
  • Syntax checking
  • DNS checking
  • Block-list checking (e.g. spamhaus)
  • Web infrastructure checking
  • Mailbox checking
    

     

• Unrivalled coverage - Email Hippo leverages the advantages of its scalable infrastructure to provide coverage of domains that are technically challenging. Consumer facing domains tend to be more challenging to cover then business facing domains B2C domains.

• Disposable email address detection - Unrivalled disposable email address detection built on Email Hippo’s proprietary multi-vector real-time analysis:

  • Real-time detection of disposable email address providers that employ obfuscation techniques (e.g. rotating domains, IP addresses and MX servers)
  • Checking against static lists
    

     

    
    

• Gibberish detection

  • A common vector for persons wishing to remain anonymous is to register or use a pre-existing domain. Finding an available domain is not easy and as such, many opt for a ‘Gibberish’ domain such as sdfre45321qaxc.com.
  • Email Hippo detects gibberish in both the user and domain elements of an email address.

     

• Domain age - Email Hippo's WHOIS service contributes valuable domain age information to help evaluate the credibility of domains.

• IP address - Email Hippo digs into the IP address to understand its origin and reputation.

• Proprietary scoring and risk assessment - All the information is wrapped into our Hippo Trust Score. A simple score between 0 and 10 rates your visitor so you can decide whether and how you treat your visitor.

• Consumer or Business assessment - Email Hippo assesses whether the email address is likely to be from a consumer or a business and presents the result as a score from 0 to 10. The closer the score is to 0 the more likely the email address belongs to a consumer, the closer it is to 10 the more likely it is to belong to a business.

ASSESS Edition 1

Specification

Concurrency

To preserve the operational integrity of the service to all of our customers, there is a maximum concurrency enforced by our systems.

Limits

Allowed throughput is 220 ASSESS requests per second.

Throughput exceeding these limits will receive HTTP response code 429 (too many requests) for subsequent requests for a duration of one minute.

Suggestions on how to manage throughput

If you experience or anticipate exceeding throughput limits, here are two ways to control query rates:

• Test your integration with representative production loads over a period of time. Monitor response codes for any 429’s. If you see any 429’s please reduce the rate at which your application is querying our servers.

• For applications that can tolerate slight delays in your data processing mesh, consider using queuing infrastructure with a rate controllable processor. Your ‘processor’ can then schedule picking work off the queue and submitting requests to our systems at a controllable rate.

Large throughput requirement

For sustained throughput of more than 220 requests per second, please contact us about a private, dedicated service.

Authentication

Email Hippo ASSESS uses API keys to allow access to the API. API keys can be managed within Hippo World.

Email Hippo ASSESS expects the API key to be included in all API requests to the server.

{k}: yourlicensekey

Endpoint - GET quota usage

* © 2020, Email Hippo Limited. (http://emailhippo.com)

# You can also use wget
curl -X GET https://api.hippoassess.com/v1/quota/{apiKey} \
  -H 'Accept: application/json'

/*
* © 2020, Email Hippo Limited. (http://emailhippo.com)
*/

<?php

require 'vendor/autoload.php';

$headers = array(
    'Accept' => 'application/json',
);

$client = new \GuzzleHttp\Client();

// Define array of request body
$request_body = array();

try {
    $response = $client->request('GET','https://api.hippoassess.com/v1/quota/{apiKey}', array(
        'headers' => $headers,
        'json' => $request_body,
       )
    );
    print_r($response->getBody()->getContents());
 }
 catch (\GuzzleHttp\Exception\BadResponseException $e) {
    // handle exception or api errors.
    print_r($e->getMessage());
 }

?>

const headers = {
  'Accept':'application/json'
};

fetch('https://api.hippoassess.com/v1/quota/{apiKey}',
{
  method: 'GET',

  headers: headers
})
.then(function(res) {
    return res.json();
}).then(function(body) {
    console.log(body);
});

URL obj = new URL("https://api.hippoassess.com/v1/quota/{apiKey}");
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
con.setRequestMethod("GET");
int responseCode = con.getResponseCode();
BufferedReader in = new BufferedReader(
    new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
    response.append(inputLine);
}
in.close();
System.out.println(response.toString());

require 'rest-client'
require 'json'

headers = {
  'Accept' => 'application/json'
}

result = RestClient.get 'https://api.hippoassess.com/v1/quota/{apiKey}',
  params: {
  }, headers: headers

p JSON.parse(result)

# © 2020, Email Hippo Limited. (http://emailhippo.com)

import requests
headers = {
  'Accept': 'application/json'
}

r = requests.get('https://api.hippoassess.com/v1/quota/{apiKey}', headers = headers)

print(r.json())

package main

import (
       "bytes"
       "net/http"
)

func main() {

    headers := map[string][]string{
        "Accept": []string{"application/json"},
    }

    data := bytes.NewBuffer([]byte{jsonReq})
    req, err := http.NewRequest("GET", "https://api.hippoassess.com/v1/quota/{apiKey}", data)
    req.Header = headers

    client := &http.Client{}
    resp, err := client.Do(req)
    // ...
}

/*
* © 2020, Email Hippo Limited. (http://emailhippo.com)
*/

using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Threading.Tasks;
using Newtonsoft.Json;

/// <<summary>>
/// Example of Http Client
/// <</summary>>
public class HttpExample
{
    private HttpClient Client { get; set; }

    /// <<summary>>
    /// Setup http client
    /// <</summary>>
    public HttpExample()
    {
      Client = new HttpClient();
    }

    /// Make a dummy request
    public async Task MakeGetRequest()
    {
      string url = "https://api.hippoassess.com/v1/quota/{apiKey}";
      var result = await GetAsync(url);
    }

    /// Performs a GET Request
    public async Task GetAsync(string url)
    {
        //Start the request
        HttpResponseMessage response = await Client.GetAsync(url);

        //Validate result
        response.EnsureSuccessStatusCode();

    }




    /// Deserialize object from request response
    private async Task DeserializeObject(HttpResponseMessage response)
    {
        //Read body 
        string responseBody = await response.Content.ReadAsStringAsync();

        //Deserialize Body to object
        var result = JsonConvert.DeserializeObject(responseBody);
    }
}

Retrieves the current usage details for a given license key.

GET //api.hippoassess.com/quota/{apiKey}

GET QUOTA record.

Parameters

Responses (including errors)

QuotaRecord schema

{
  "quotaUsed": 0,
  "quotaRemaining": 0,
  "nextQuotaResetDate": "2018-08-09T10:26:42Z",
  "reportedDate": "2018-08-09T10:26:42Z"
}

Endpoint - GET ASSESS result

* © 2020, Email Hippo Limited. (http://emailhippo.com)

# You can also use wget
curl -X GET https://api.hippoassess.com/v1/json/{apiKey}/{emailAddress}/{ipAddress}/{firstName}/{lastName} \
  -H 'Accept: application/json'

/*
* © 2020, Email Hippo Limited. (http://emailhippo.com)
*/
<?php

require 'vendor/autoload.php';

$headers = array(
    'Accept' => 'application/json',
);

$client = new \GuzzleHttp\Client();

// Define array of request body.
$request_body = array();

try {
    $response = $client->request('GET','https://api.hippoassess.com/v1/json/{apiKey}/{emailAddress}/{ipAddress}/{firstName}/{lastName}', array(
        'headers' => $headers,
        'json' => $request_body,
       )
    );
    print_r($response->getBody()->getContents());
 }
 catch (\GuzzleHttp\Exception\BadResponseException $e) {
    // handle exception or api errors.
    print_r($e->getMessage());
 }

?>

const headers = {
  'Accept':'application/json'
};

fetch('https://api.hippoassess.com/v1/json/{apiKey}/{emailAddress}/{ipAddress}/{firstName}/{lastName}',
{
  method: 'GET',

  headers: headers
})
.then(function(res) {
    return res.json();
}).then(function(body) {
    console.log(body);
});

URL obj = new URL("https://api.hippoassess.com/v1/json/{apiKey}/{emailAddress}/{ipAddress}/{firstName}/{lastName}");
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
con.setRequestMethod("GET");
int responseCode = con.getResponseCode();
BufferedReader in = new BufferedReader(
    new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
    response.append(inputLine);
}
in.close();
System.out.println(response.toString());

require 'rest-client'
require 'json'

headers = {
  'Accept' => 'application/json'
}

result = RestClient.get 'https://api.hippoassess.com/v1/json/{apiKey}/{emailAddress}/{ipAddress}/{firstName}/{lastName}',
  params: {
  }, headers: headers

p JSON.parse(result)

# © 2020, Email Hippo Limited. (http://emailhippo.com)

import requests
headers = {
  'Accept': 'application/json'
}

r = requests.get('https://api.hippoassess.com/v1/json/{apiKey}/{emailAddress}/{ipAddress}/{firstName}/{lastName}', headers = headers)

print(r.json())

package main

import (
       "bytes"
       "net/http"
)

func main() {

    headers := map[string][]string{
        "Accept": []string{"application/json"},
    }

    data := bytes.NewBuffer([]byte{jsonReq})
    req, err := http.NewRequest("GET", "https://api.hippoassess.com/v1/json/{apiKey}/{emailAddress}/{ipAddress}/{firstName}/{lastName}", data)
    req.Header = headers

    client := &http.Client{}
    resp, err := client.Do(req)
    // ...
}

/*
* © 2020, Email Hippo Limited. (http://emailhippo.com)
*/

using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Threading.Tasks;
using Newtonsoft.Json;

/// <<summary>>
/// Example of Http Client
/// <</summary>>
public class HttpExample
{
    private HttpClient Client { get; set; }

    /// <<summary>>
    /// Setup http client
    /// <</summary>>
    public HttpExample()
    {
      Client = new HttpClient();
    }

    /// Make a dummy request
    public async Task MakeGetRequest()
    {
      string url = "https://api.hippoassess.com/v1/json/{apiKey}/{emailAddress}/{ipAddress}/{firstName}/{lastName}";
      var result = await GetAsync(url);
    }

    /// Performs a GET Request
    public async Task GetAsync(string url)
    {
        //Start the request
        HttpResponseMessage response = await Client.GetAsync(url);

        //Validate result
        response.EnsureSuccessStatusCode();

    }


    /// Deserialize object from request response
    private async Task DeserializeObject(HttpResponseMessage response)
    {
        //Read body 
        string responseBody = await response.Content.ReadAsStringAsync();

        //Deserialize Body to object
        var result = JsonConvert.DeserializeObject(responseBody);
    }
}

Performs email address verification to the full data enrichment level and returns the data in four formats:

• JSON     GET //api.hippoassess.com/v1/json/{apiKey}/{emailAddress}/{ipAddress?}/{firstName?}/{lastName?}

• BSON     GET //api.hippoassess.com/v1/bson/{apiKey}/{emailAddress}/{ipAddress?}/{firstName?}/{lastName?}

• XML     GET //api.hippoassess.com/v1/xml/{apiKey}/{emailAddress}/{ipAddress?}/{firstName?}/{lastName?}

• Protobuf   GET //api.hippoassess.com/v1/proto/{apiKey}/{emailAddress}/{ipAddress?}/{firstName?}/{lastName?}

GET ASSESS result.

Parameters

Responses (including errors)

Result record schema

{
    "version": {
        "v": "ASSESS-(0.0.1)",
        "doc": "https://docs.hippoassess.com/"
    },
    "meta": {
        "lastModified": "string",
        "expires": "string",
        "email": "string",
        "emailHashMd5": "string",
        "emailHashSha1": "string",
        "emailHashSha256": "string",
        "firstName": "string",
        "lastName": "string",
        "domain": "string",
        "ip": "string",
        "tld": "string"
    },
    "hippoTrust": {
            "score": 0
    },
    "userAnalysis": {
        "syntaxVerification": {
            "isSyntaxValid": true
        },
        "disposition": {
            "isGibberish": true,
            "isProfanity": true,
            "gender": "string"
        }
    },
    "emailAddressAnalysis":{
        "mailboxVerification": {
            "result": "string",
            "secondaryResult": "string"
        },
        "syntaxVerification": {
            "isSyntaxValid": true
        },  
        "disposition": {
            "isGibberish": true,
            "isProfanity": true,
            "isRole": true,
            "isSubaddressing": true,
            "isFreeMail": true,
            "hasCatchAllServer": true,
            "hasBeenBlocked": true
        },
        "assessments": {
            "consumerBusiness": 0
        }
    },
    "domainAnalysis":{
        "disposition": {
            "isSubDomain": true,
            "isGibberish": true,
            "isProfanity": true,
            "isDarkWeb": true,
            "hasBeenBlocked": true,
            "hasDnsRecords": true,
            "hasMxRecords": true,
            "mailServerLocation": "string",
            "mailServerInfrastructure": "string"
        },
        "age": {
            "text": "string",
            "seconds": 0,
            "iso8601": "string"
        },
        "registration": {
            "ownerContactName": "string",
            "ownerContactCity": "string",
            "ownerContactCountry": "string"
        }
    },
    "ipAddressAnalysis":{
        "disposition": {
            "isTorExitNode": true,
            "hasBeenBlocked": true
        },      
        "location": {
            "latitude": 0,
            "longitude": 0,
            "timeZone": "string",    
            "continent":{
                "code":"string",
                "name":"string"
            },
            "country":{
                "code":"string",
                "name":"string",
                "isInEU": true, 
                "currencies": [
                    "string"
                ],
                "dialingCodes": [
                    "string"
                ]
            },
            "city":{
                "name":"string"
            }
        },
        "dataCenter":{
            "autonomousSystemNumber": 0,
            "autonomousSystemOrganization": "string",
            "connectionType": "string",
            "isp": "string",
            "organization": "string"
        }
    }
}

Result codes

Primary mailbox result codes

Secondary mailbox result codes

Email Hippo Trust Score

The Trust Score provides an ‘at a glance’ determination of quality; drilling deeper than just the email address itself.

The Email Hippo Trust Score is designed to answer a fundamental question posed from the perspective of a business owner, merchant, data broker or lead generation service:

• How much can I trust the person associated with this email address and optionally ip address?

The Trust Score takes dozens of metrics and signals into consideration when making this assessment and providing the final score.

Consumer Business assessment

The Consumer Business Assessment rates the liklihood that the email address belongs to a consumer or a business.

The closer the score is to 0 the more likely the email address relates to a consumer.

The closer the score is to 10 the more likely the email address relates to a business.

.Net client libraries

We have a .NET package built for easy integration with our ASSESS Edition 1 (v1) API services. For further information on the RESTful server side implementation, please see the docs and schema.

If you're working in the .NET environment, this package can save you hours of work writing your own JSON parsers, message pumping logic, threading and logging code.

How to get the package

The package is available from Nuget.

Frequently asked questions

How can I get a key?

Click here to sign up and generate a key.

Can I trust you with my data?

Great question. Yes, of course - see our Compliance pages for detailed information.

Will I get blocklisted using your APIs?

No. It’s Email Hippo infrastructure that does the work.

Will anyone know that I am querying an email address, a domain or an ip address?

No. It’s Email Hippo infrastructure that does the work.

How do I call your APIs?

For a JSON response, make a simple GET request to the endpoint.

Read the endpoint sections for more information and take a look at the code samples, or try it out when you sign up.

Does the system get slower when it’s busy?

No. All infrastructure is hosted in cloud based platforms with automatic scaling enabled. Automatic scaling kicks in at busy times to provide more hardware resources to meet demand.

Do you cache results?

To deliver the speed and reliability demanded by our customers, verification results are cached as follows:

• Level 1 cache: CloudFlare based. Cache expiration 2 hours.

• Level 2 cache: Microsoft Azure based - see table below

No personally identifiable information is stored in our cache infrastructure.

Can I get my usage in real-time?

Usage is available in the Hippo World customer portal or through the ASSESS quota API.

What comes back from the API?

Various text or binary response formats.

Note: For a detailed explanation of the responses available, see the appropriate service Edition/Version Schema on this site.

Glossary

ACL

Access Control List.

An ACL determines what networking traffic is allowed to pass and what traffic is blocked.

An ACL change is sometimes required to your company firewall in order to access our API.

API

Application Programmers Interface.

See Wikipedia - API Definition for further information.

B2B

Business To(2) Business

Business email hosting services are generally private, enterprise grade hosting services typically hosted in either private data centers or in cloud based infrastructure.

Business to business refers to the activity of businesses sending email to clients using business email addresses.

B2C

Business To(2) Consumer

Consumer email hosting providers are generally well known, mostly web based providers such as Outlook, Yahoo, AOL, Gmail etc.

Business to consumer refers to the activity of businesses sending email to clients using consumer email addresses.

Verifying email addresses in consumer domains is generally more technically challenging than B2B

Block list

See DNSBL.

BSON

Binary Object Notation

See Wikipedia - BSON for further information.

CORS

Cross Origin Resource Scripting

Allows modern browsers to work with script (e.g. JavaScript) and JSON data originating form other domains.

CORS is required to allow client script such a JavaScript, jQuery or AngularJS to work with results returned from an external RESTful API.

See Wikipedia - CORS for more information.

DDoS

Distributed Denial of Service

See Wikipedia - Denial-of-service attack for further information.

DEA

Disposable Email Address

There are many services available that permit users to use a one-time only email address. Typically, these email addresses are used by individuals wishing to gain access to content or services requiring registration of email addresses but same individuals not wishing to divulge their true identities (e.g. permanent email addresses).

DEAs should not be regarded as valid for email send purposes as it is unlikely that messages sent to DEAs will ever be read.

DNS

Domain Name System

At its simplest level, DNS converts text based queries (e.g. a domain name) into IP addresses.

DNS is also responsible for providing the MX records needed to locate a domains mail servers.

See Wikipedia - Domain Name System for further information.

DNSBL

DNS Block List

As an anti-spam measure, mail servers can use spam block lists to ‘look up’ the reputation of IP addresses and domains sending email. If an IP or domain is on a block list, the mail server may reject the senders email message.

See Wikipedia - DNSBL for further information.

ESP

Email Service Provider

A service that sends emails on your behalf.

See Wikipedia - Email service provider (marketing) for more information.

Free mail

Addresses served by popular B2C service providers such as Outlook, Yahoo, Live, AOL, Gmail and so on.

Greylisting

A technique used in mail servers as an anti-spam technique. Sometimes also known as “deferred”, greylisting arbitrarily delays the delivery of emails with a “try again later” response to the client sending the email.

See Wikipedia - Greylisting for more information.

HTTP

Hypertext Transfer Protocol

See Wikipedia - Hypertext Transfer Protocol for more information.

IP address

Internet Protocol Address

See Wikipedia - IP Address for more information.

ISO 3166

International standard for country codes.

See Country Codes - ISO 3166 for more information.

JSON

JavaScript Object Notation

JavaScript Object Notation, is an open standard format that uses human readable text to transmit data objects consisting of attribute value pairs. It is used primarily to transmit data between a server and web application.

See Wikipedia - JSON for more information.

License key

License key authentication is best for situations where simplicity is required and you can keep the key private. An ideal use case for key authentication would be for server based applications calling the RESTful API.

Click here to sign up and access a license key.

ms

Milliseconds.

MX

Mail Exchanger

The MX is a server responsible for email interchange with a client.

NDR

Non Delivery Report

A message that is returned to sender stating that delivery of an email address was not possible.

See Wikipedia - Bounce message for more information.

Office 365

Office 365 mail servers (e.g. x-com.mail.protection.outlook.com) are always configured with the catch all policy, accepting all emails sent to the domain and redirecting them to a central email box for manual inspection. Catch all configured servers cannot respond to requests for email address verification.

This does not affect our coverage of Hotmail, Live and Outlook mailboxes.

protobuf

Protocol Buffers is a method of serializing structured data.

See Wikipedia - Protocol Buffers for more information.

Punycode

Punycode is a way to represent Unicode with the limited character subset of ASCII supported by the Domain Name System.

See Wikipedia - Punycode for more information.

RESTful

Representational state transfer

See Wikipedia - RESTful for more information.

RFC

Request for Comments

The principal technical development and standards-setting bodies for The Internet.

See Wikipedia - Request for Comments for more information.

Role address

A role address is a generic mailbox such as info@, sales@ used by organizations to manage email messages of similar organizational types. For example, email messages sent to sales@ can be routed to an organizations sales team where a team of sales people can deal with enquiries.

Role addresses allow collaborative working based on groups rather than indiviidual mailboxes.

SLA

Service Level Agreement

See Wikipedia - SLA for more information.

See our Service Level Agreement.

SMTP

Simple Mail Transport Protocol

SMTP is a protocol. It is the sequence of commands and responses between a client (the software sending an email) and server (the software receiving an email) that facilitates the sending and receiving of email between computer based email messaging systems.

Spam trap

Spam traps are email addresses used for the sole purpose of detecting spamming activities.

Spam traps are used by many block lists (DNSBL) to detect spammers.

See Wikipedia - Spam traps for more information.

TXT

TXT records associate arbitary and unformatted text with a domain. TXT records uses include Sender Policy Framework (SPF) and other domain validation applications.

See Wikipedia - TXT record for more information.

XML

e(X)tensible Markup Language

See Wikipedia - XML for more information.